Envelope



Patented May 16, 1939 PATENT OFFICE ENVELOPE Robert L. Gray, Brooklyn,N. Y.

Original application June 14, 1933, Serial No. 675,689. Divided and thisapplication December 11, 1937, Serial No. 179,251

8 Claims.

This invention relates to methods of making envelopes, and moreparticularly to a method for adhesively uniting a patch, comprisingsubstantially transparent material over a cutout in an envelope blank toform window envelopes, or similar containers.

In the production of window envelopes of the two-piece type,whichcomprises an envelope blank of paper and the separately formedpatch of substantially transparent material, existing methods foruniting the patch to the envelope blank comprises essentially, theapplication of a fluid adhesive between the patch and the envelope blanksurrounding the cutout, the contact ing of the patch to the envelopeblank being followed by envelope forming operations in which foldingover of back flaps and side flaps into envelope forming positionsubstantially completes the envelope forming operations.

Existing methods as known to me which utilize previously formed envelopeblanks having a window cutout formed therein, unite the patch to coverthe cutout by steps comprising essentially the application of a small orlimited quantity of wet adhesive to the envelope blank surrounding thecutout, and then overlying apatch of substantially transparent materialto contact the same with the adhesive. By this method, the completion ofthe envelope follows immediately after the patch-applying steps. Theapplication of moist adhesive is accomplished by an applicator oroutlining die which limits the moist adhesive in spaced relationshipfrom the periphery of the cutout and from the periphery of the patch.This method of application is not only one of convenience, but also oneof necessity, in View of the fact that if greater quantities of adhesiveare used, any attempt to align the patch with the outline of theadhesive that is applied, results in the extrusion of the adhesivebeyond the periphery of the patch. Such excess material would result inadhesively uniting the side or back flaps to the front of the envelope.This limitation as to the distribution of the adhesive between the patchand the envelope blank results in an envelope in which loose edges areprovided on the interior of the envelope which interfere with theinsertion of material therein when the envelope is completely formed,and which is further objectionable in that there are formed looseperipheral edges around the cutout which are likely to snag othermaterials or envelopes sorted or handled at the same time. Any attemptto register the application of the film of adhesive with the edge of thepatch have been unsuccessful, as the subsequent pressure for uniting thepatch to the blank carrying the adhesive distributes the adhesive in anuncontrolled manner. While the use of a free-flowing adhesive isdesirable in that theminimum amount of contact 5 is necessary to locatethe patch, the free-flowing characteristics of the adhesive haveresulted in having the trade accept window envelopes of the two-piecetype with this deficiency, at a sacrifice of efiiciency in the use ofthe envelope, and not- 10 withstanding the advantages involved in theproduction of a two-piece envelope from a separately formed blank andpatch which permits any quality of paper to be used for the envelopeblank and a more efficient and more highly transparent l5 patch for thewindow part or patch thereof.

It is therefore a object of my invention to provide a methodforadhesively uniting a patch comprising substantially transparentmaterial, to a separately formed paper envelope blank by con- 20trolling the application of the adhesive necessary for uniting the patchto the envelope blank, to unite aperipheral edge of the patch to theblank without any loose edges which may interfere with the insertion ofmaterial into the completely formed envelope.

It is further contemplated as an object of my invention to provide amethod for adhesively uniting a patch to an envelope blank, utilizingfree-flowing adhesive material and to effect a union between the patchand the envelope blank by means of a free-flowing adhesive, operatingunder conditions registering a peripheral edge of the patch to theapplication of the film of adhesive material, whereby loose edges of thepatch in the direction of the filling side of the envelope are avoided,and without the' extrusionv of extraneous adhesive which would otherwiseprevent the rapid succession of operations following said patch-unitingoperation and constituting the 40 envelope forming steps which includefolding over said patch so united, the envelope forming flaps.

It is a further object of my invention to provide a method for uniting aseparately formed envelope blank including a cutout, utilizing a free-45 flowing adhesive, and unite a peripheral edge of the patch to theface of the envelope blank, or the-peripheral edges of the cutout to theface of the patch, without any loose edges, by controlling theapplication of pressure to the peripheral edge which is united to thecontacting face ofv the overlyingweb of material so as to cause theadhesive to fiow away from the periphery edge at the time that pressureis applied for contacting the adhesive interposed between the separatelayers of paper and transparency.

To attain these objects and such further objects as may appear herein orbe hereinafter pointed out, reference will now be made to theaccompanying drawing forming a part hereof, in which- Figure 1 is a planview of an envelope blank at the initial step of the method;

Figure 2 is a similar view with a patch applied;

Figure 3 is an enlarged fragmentary, sectional view diagrammaticallyillustrating the pressing operation of the patch to the envelope blank;

Figure 4 is an enlarged sectional view of the joint resulting therefrom.

Making reference to the drawing, 1 provide an envelope blank l0,comprising side flaps II and I2 and back flap l3 and the usual sealingflap M. This blank is provided with a cutout IS. A blank of thischaracter is of the type usually employed in making window envelopes ofpaper, and in this condition is ready for the existing machinery forapplying the patch to form a window envelope.

The preferred operation following the provision of the blank as thus fardescribed, is the application of a film of adhesive l6 and I1 applied tothe back flap and sealing flap, respectively. This film of adhesive isthe one usually employed in the construction'of envelopes and may beapplied by applicators which limit the adhesive to an area around theperipheral portions of the flaps, in the customary manner. At thisstage. I also apply adjacent the cutout I 5, an application of a coatingof adhesive H3. The applicator for this purpose outlines a substantiallystraight edge I9 adjacent the filling side of the envelope, which isadjacent the sealing flap l4. 7

Where, in the subsequent application of the patch as contemplated by mefor forming a window envelope, the transparency isa patch ofsubstantially rectangular shape, the film of adhesive 18 is made by theapplication whic h deposits a substantial trapezoidal outline, theextreme corners whereof, 20 and 2|, are substantially the length of thepatch to be applied. The lateral sides 22 and 23 taper sharplydownwardly towards the bottom of the envelope. With the blank treated asthus described, and while the adhesive film I8 is still moist, a plungeror plate P carrying a patch 24 is brought into position so that the edge28 thereof is brought into registry with the edge IQ of the film ofadhesive l8. The patch is preferably of a length corresponding to thedistance between the points 20 and 2 l though it may be slightly longerthan this dimension.

The plunger or plate is brought into proximity to the blank H] by areciprocating action, and as in existing apparatus, serves to carry thepatch by suction. As the plunger or plate reaches the supporting basecarrying the blank ID, the suction is released from the chamber 26 andtransferred in one form of the construction of the apparatus used to thesupporting base for the blank l0 operating adjacent the cutout l5.Substantially simultaneously with this action, the plate or plungerfirst contacts the edge 28 of the patch 24 with the edge I9 of-the filmof adhesive I8, and at the point 21 on the blank [0. The plate orplunger P continues in its downward movement by a slight rolling action(or a slight canting action being employed for a flat face plunger)displacing the moist adhesive l8 from the'point 19 towards the cutoutIS. The rolling or canting action just described and the fact that thearea between the point 21 and the edge of the patch 28 is substantiallyentrapped, will prevent displacement or extrusion of the adhesive in adirection beyond the edge 28 of the patch. As the rolling and pressingaction continues, the adhesive i8 interposed between the patch 24 andthe blank will spread in the direction of the rolling action. Theoutlines of the adhesive at the lateral sides 22 and 23 will flow tosome extent, beneath the patch 24 adjacent the lateral sides 29 and 30,respectively.

However, the angular relationship of the lateral edges 22 and 23 of theadhesive are so chosen that any flow of the adhesive which occurs willremain within the boundary outlined by the patch 24 adjacent the lateraledges 29 and 3E), and will not be extruded beyond the same.

The same rolling action presses the adhesive away from the lower edge15a of the cutout, and the width of the patch 24 is positioned so thatits lower edge 29a will more than cover any adhesive extruded in thedirection of this edge. The edge 29a may hang loose and since it ispositioned away from the filling side of the envelope, it will in no wayinterfere with the insertion of any material in a completely formedenvelope. However, extending beyond any position which may be assumed bythe adhesive film, it will not interfere with the subsequentenvelope-forming operations.

By the pressing operation as just described, some of the adhesive may beextruded beyond the forward edge l5b of the cutout formed in the blankH] to produce a fillet 38 at this point. However, this will notinterfere with the handling of the envelope, as beneath the cutout ISthe supporting table is formed with sufficient clearance to avoid anyadhesive contact of the adhesive formed by the fillet 30 with thesupporting table for carrying out this operation. To further assureagainst any interference, by reason of this extruded material, thesupporting table adjacent the cutout [5 may be provided with means forrapidly, completely or superficially dehydrating the small fillet ofadhesive which is thus extruded, and for this purpose, heating means maybe positioned adjacent this point. The attachment of the patch as thusdescribed permits the use of a free-flowing adhesive with the obviousadvantages that Very slight contact is necessary and thereby permittinga high order of speed of operation. The control of the flow of theadhesive all within the periphery of the patch permits theenvelope-forming operations to follow immediately thereafter, so thatthe side flaps II and I2 and the back flap I3 may be folded over intoenvelope-forming position, while the adhesive uniting the patch is stillmoist, without danger of connecting the back of the envelope thus formedfrom the flaps H, 12 and I3, to the front face of the envelope blankwhich carries the patch. It will thus be observed that I have provided amethod for uniting the patch to the envelope blank, in which theadhesive adjacent the periphery edge of the patch nearest to the fillingside of the envelope and the patch may be brought into registry witheach other, without fear of extruding the adhesive beyond the edge ofthe patch, by reason of the rolling action in pressing the edge of thepatch into position, and I consider it within the scope of my inventionto adhesively unite two materials in face contact wherein the peripheryor edge of one material contacts the face of another by the rolling andpressing operation heretofore described, wherein the interposed film offree-flowing adhesive is caused to flow away from the edge of thematerials united.

While I prefer by my process to register a periphery of the patchadjacent the filling sideof the envelope with an application of normallymoist adhesive applied to the envelope or container blank, to adhere thepatch to the envelope or container blank without loose edgesinterferingwith the filling of the envelope or container adjacent thefilling side, a moist condition of adhesive may be similarly used on thepatch of transparent or translucent sheeting; and While either of suchpractices may be adopted as the preferred practice, it is contemplatedby me to also or alternatively seal the periphery of the cutout in theenvelope blank and container to the overlapping patch to avoid looseedges at the periphery of the cutout. Under such procelure, where it isfound for mailing or handling purposes, that the sealing of theperipheral edges of the cutout to the patch is a desirable feature, theabove entitled procedure may include uniting the paper or containersurface adjacent a peripheral edge of the cutout to the surface of theoverlapping patch. Under such condition of operation, the adhesive inthe moist condition is applied to the surface of the paper forming theenvelope blank or container adjacent the periphery of the cutout or thatportion of the paper or container blank outlining the cutout. Uponoverlying the patch or sheet of transparency, such as Cellophane orglassine paper or substantially simultaneously therewith the pressurefor uniting the patch begins adjacent the cutout peripheries and thedistributing pressure continues away from the peripheries of the cutoutin the continuous application of the pressure. Such action serves topartially flow the moist adhesive away from the cutout to the overlapbetween the patch and fabric of the envelope, blank or container. Theamount of adhesive used is to confine the adhesive within the confinesof the patch.

My invention, in its broader aspects, therefore has as one of itsobjectives, the adhesion of a peripheral edge of fabric of the characterset forth, to an overlapping sheeting by the use of an adhesive film ina moist condition, which includes pressing the two sheets in positionwith the interposed adhesive in a moist condition, the pressure beingprogressively applied from a point beginning at the periphery and thenfor a certain distance away from the periphery to distribute theadhesive away from the periphery rather than extrude the adhesive inmoist condition beyond the periphery, which may objectionably accumulatethe adhesive.

While I have described my invention in its preferred embodiment, asapplied to a separately formed patch and envelope blank containing acutout in which each of these sheets is separately formed, I consider myinvention to have a wider application, all coming within the scope ofthe appended claims.

This application is a division of my application Serial No. 675,689,filed June 14, 1933, now Patent No. 2,101,847, granted December 14,1937.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent is- 1. A window envelopecomprising a separately formed envelope blank and separately formedpatch overlying a cutout, said patch being adhesively united to theenvelope blank by a film of adhesive from an edge of the patch adjacentthe filling side of the envelope, the film uniting the patchprogressively decreasing in area towards the cutout portion.

2. A window envelope comprising a separately formed envelope blankincluding a cutout and a separately formed patch, said patch beingadhesively united to the envelope blank along the rectilinear lineadjacent the filling side of the envelope without any loose edges, theadhesive film uniting the patch to the envelope blank extending from a.peripheral edge of the patch adjacent the filling side of the envelopein decreasing amounts within the confines of the patch in a directiontowards the cutout.

3. A window envelope comprising a separately formed envelope blankincluding a cutout, a substantially transparent patch overlying saidoutout and forming an overlapping portion, said overlapping portionadjacent the filling side of the envelope being united to the envelopeblank from a peripheral edge without any loose edges the adhesive filmbeing insufficient to completely unite other overlapping portions of thepatch.

4. A window envelope comprising a separately formed envelope blankincluding a. cutout, a substantially rectangular patch overlying saidoutout, the peripheral edge of said patch adjacent the filling side ofthe envelope being adhesively united to the envelope blank without anyloose edges by an adhesive film, the film being interposed between saidpatch and envelope blank in diminishing quantities extending within theconfines of the patch from the peripheral edge towards the bottom of theenvelope.

5. A container of the window envelope type comprising a separatelyformed container blank including a cutout, a substantially transparentpatch overlying said cutout, said patch being adhesively united to thecontainer blank by a film of a water soluble adhesive from a peripheralportion of the patch adjacent the filling side of the container, thefilm uniting the patch leaving lateral peripheral portions of the patchfree.

6. A windowed container of the envelope type comprising a separatelyformed blank having a cutout and a separately formed patch overlying thecutout, said patch being adhesively united to the blank to overlap thecutout by a film of a gum adhesive, uniting the patch from a peripheraledge thereof adjacent the filling side of the container substantiallythroughout a rectilinear line without any loose edges, the adhesionbetween the patch and the blank at lateral peripheral edges of the patchbeing confined to leave said lateral peripheral edges of the patchunsealed.

'7. A windowed container of the envelope type having a filling sidecomprising a separately formed blank having a cutout and a separatelyformed patch of substantially transparent material overlapping thecutout, said patch being adhesively united to the blank within the areadefined by the overlapping portion by a film of gum adhesive uniting thepatch to and from a substantial portion of the peripheral edge of thepatch adjacent the filling side of the container without any loose edgesadjacent the filling side of the container which may interfere with thefilling of said container, the adhesion between the patch and the blankadjacent lateral peripheral edges of the patch being confined short ofsaid peripheral edges, leaving said lateral peripheral portions of thepatch free and unsealed and into which unsealed portions excess adhesivemay collect.

8. A container of the window envelope type comprising a separatelyformed container blank including a cutout, a substantially transparentpatchzoverlying saidicutoutr, saidspatchtbeing adhesively; united 15;the: container blank.- by' a; flimof= adheeiveawhichisthe residuum:offamadhesi'ye in; a vnlatile vehicle; said; film: being interposedbetween: the patch and the: container body: and lying: from aperipheral; portion of; the patch: ad jacent; the filling side at theenvelopeancf en mnmaaa:

compassed by the area; covered by said patch, uniting thepatch to. leavelateral peripheral portions-of: the patch free, thafilm ofadhesive beinginsuflici'ent teextrude beyond. the edges of the patch at thelateral:peripheral portions of 5 the patch.

ROBT. L. GRAY.

